I got really heavy into chat rooms last year, something i never did before. First was google lively, where i met one of the best friends i ever had. Lively has shut down though.
Next was Second Life. I stopped using it so much because I have other things to do. However it is addictive. Amazingly enough, you can spend months on second life and never talk to anyone. It's almost like real life, you go into a place where there is lots of people but you won't talk to them. They'll go about their business like it's real life where people just pass each other on the street, etc. But I spent a lot of time just exploring the vastness of it, as well as customizing characters, which is very good.
I tried to do a few RPG on 2nd life. Since it is open-ended virtual world and not a real "game", you have to either type out your rpg (like if you were playing paper and pen rpg) or a place will offer you a database-run life meter/level meter, depending on which sim you go to. Some sims just give you rpg virtual dice. Anyway, RP on 2nd life can be incredible fun, but it's very social-based and actually since i am too scared to talk mostly I just watch. A few times I have actually role played with people and it was incredible fun but it takes a long time because you have to type everything.
Since you aren't competing with people or trying to get a task done, these chat rooms seem to be less aggressive but you still get lots of jerks too.